With the technology development and the increasing demand for mobile devices, the demand for batteries as an energy source is dramatically increasing, and in keeping up with this movement, many studies are being made on batteries to meet diverse demands.
Typically, batteries may be classified into a can-type secondary battery and a pouch-type secondary battery based on the case type.
In this instance, a pouch-type secondary battery includes a pouch case, an electrode assembly, and an electrode tab. The pouch case may be formed with a sufficient size to accommodate the electrode assembly, the electrode tab, and an electrode lead to be described below.
The electrode assembly includes a cathode plate, an anode plate, and a separator. The electrode assembly may have the cathode plate and the anode plate stacked in a sequential order with the separator interposed between the cathode plate and the anode plate. The electrode assembly typically includes, for example, a jelly-roll (wound) electrode assembly having a structure in which long sheet-type cathodes and anodes are wound with separators interposed therebetween, a stack-type electrode assembly having a structure in which a plurality of cathodes and anodes cut to a predetermined size are stacked in a sequential order with separators interposed therebetween, and a stack/folding-type electrode assembly having a structure in which bicells or full cells including a predetermined unit of cathodes and anodes stacked with separators interposed therebetween are folded.
The electrode tab extends from the electrode assembly. In this instance, the electrode tab may be connected to other component such as the electrode lead (not shown) while not being directly exposed to the outside of the pouch case.
The pouch-type secondary battery may be used singularly, but to increase the capacity or power, is often used by electrically connecting a plurality of pouch-type secondary batteries.
Here, the plurality of pouch-type secondary batteries constructs a secondary battery module. Thus, heat generated from each secondary battery is aggregated, and due to a dense structure of the secondary batteries, a large amount of heat is produced, and to discharge the heat, an additional structure such as a cooling pin may be included.
Also, a cartridge may be provided to fix each pouch-type secondary battery to the cooling pin in the secondary battery module.
However, in the case of this coupling structure, the size of the secondary battery module may increase, and the use of the cartridge causes a problem with an increasing number of components for coupling and a complex assembly process.